evaporative cooling ... what is it?
Remember swimming on a hot, dry day, then getting out of the water and feeling
the chill of the wind hitting your wet skin? Or simply try dipping your finger in a
glass of water, then blowing air across your finger and feeling the cool sensation as
the water evaporates. That’s evaporative cooling.
Try the same thing when there is no wind or no air moving. The surrounding air is
quickly saturated with moisture, there is no evaporation and the cooling effect is gone.
Evaporative cooling units create this naturally occurring process and provide a
constant flow of cool, refreshing air into a hot, uncomfortable environment.
how does it work?
The heart of an evaporative cooling system is the pad where the water evaporates and the
air passing through the pads is cooled.
Evaporative cooling pads, like Küül® pads, are manufactured of fluted cellulose sheets that
are glued together. This material is chemically impregnated with special compounds to
prevent rot and ensure a long service life.
A special water distribution system spreads water over the surface of the pad, ensuring a
uniform supply of water to keep the entire air contact surface thoroughly wetted. Fans create a negative pressure, causing air to be drawn through the pads.
Evaporation results from contact between air and water. A control system operates the
water pump and the fan distributes the cool air.
The relative humidity is lowest in the afternoon when the temperature is at its highest. And the lower the humidity, the better the evaporative cooling effect. In other words, the
cooling effect is best when you need it the most.
evaporative cooling vs. traditional air conditioning
Evaporative coolers and central air conditioners both serve the same important purpose:
keeping us cool. But these two systems operate very differently. Understanding the
difference can help get the most out of any system and minimize wasted energy.
Evaporative coolers cool air by filtering it through water, thus lowering the air’s
temperature. These systems work best when a small amount of outside air circulates into
the space where the evaporative cooler is employed. This also introduces fresh air into
the environment and reduces the risk of poor indoor air quality.
Central air conditioners, on the other hand, work by taking humidity out of the air.
These systems produce cold, dry air and work best in an airtight space.
The major advantage of an evaporative cooler is that its operating costs are typically
one-third those of a central air conditioner. The initial equipment cost is also lower than
air conditioners. Along with lower operating costs and simple installation, evaporative
cooling can be a perfect, ozone-friendly alternative to traditional air conditioning.
is it good for the environment?
Refrigerated cooling makes the air dry and uses refrigerants which may harm the
environment. Evaporative cooling, however, is based on a totally natural process of air
cooled by water which means it won’t dry out the air, irritate your skin, throat or eyes, or
affect the environment.
Evaporative cooling is the healthiest way to cool because it replaces stale air with
clean, fresh air many times an hour utilizing air from an outside source. The air is never
re-circulated which means smells and airborne germs are expelled.
will it save me money?
Evaporative cooling is also up to 50 percent cheaper to install and considerably cheaper to
run than refrigerated cooling.
Typically, the cost for water and electricity for a 36” unit for eight hours of operation is
less than one dollar. Smaller units will operate for longer periods for the same amount of
money.
That’s approximately three times cheaper than traditional air conditioning.
evaporative cooling and heat stress
Heat stress can occur in people, animals and even equpiment. According to the Occupational
Safety and Health Administration (OSHA) and other agencies, employees required to work in
high temperature environments should be allowed frequent breaks in a cool place to avoid
symptoms of heat stress including nausea, dizziness, cramps, confusion, unconsciousness,
seizure and even death. High temperature environments are generally referred to as those
over 87˚F for light work, over 82˚F for moderate work and over 78˚F for heavy work.
According to the “Journal of Dairy Science,” across all animal classes, the estimated
national annual losses to heat stress are estimated at $2.4 billion. In cattle, heat stress
reduces fertility and milk production in cows and can cause udder infections and
even mortality during the hot summer months. Heat stress is also to blame for a high
percentage of piglet and poultry mortality.
Evaporative cooling units, like Port-A-Cool® units, can lower the ambient temperature an
average of 20˚F, turning a restrictive 90˚F area into a comfortable 70˚F area.
For more information, please call 936-598-5651 • 1-800-695-2942
visit our website at: www.port-a-cool.com